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Colloidal bismuth therapeutics have been used for hundreds of years, yet remain mysterious. Here we report an X-ray pair distribution function (PDF) study of the solvolysis of bismuth disalicylate, a model for the metallodrug bismuth subsalicylate (Pepto-Bismol). This reveals catalysis by traces of water, followed by multistep cluster growth. The ratio of the two major species, {Bi9O7} and {Bi38O44}, depends on exposure to air, time, and the solvent. The solution-phase cluster structures are of significantly higher symmetry in comparison to solid-state analogues, with reduced off-center Bi3+ displacements. This explains why such "magic-size" clusters can be both stable enough to crystallize and sufficiently labile for further growth.
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Bismuto , Compostos Organometálicos , SalicilatosRESUMO
Transforming growth factor ß (TGF-ß) signalling pathways are highly conserved across metazoa and play essential roles not only during development but also in adult tissue maintenance. Alterations of these pathways usually result in a plethora of pathologies. In the nematode Caenorhabditis elegans, the TGF-ß Sma/Mab (small/male abnormal) pathway regulates various worm phenotypes such as body size, immune response, ageing, matricide and reproductive span. SMA-10 has been described as a positive modulator of worm body size through the TGF-ß Sma/Mab pathway. To better understand if SMA-10 is a core component of the pathway, we use gene epistatic analysis to assess the contribution of SMA-10 to various phenotypes regulated by TGF-ß Sma/Mab. We confirm that SMA-10 controls body size and find that it also affects the matricide and reproductive span of the nematodes. However, neither male tail formation (previously reported) nor ageing appeared altered. Lastly, although null sma-10 worms are more susceptible to Pseudomonas aeruginosa infections than wild-types, this response does not depend on TGF-ß Sma/Mab but on the insulin receptor DAF-2. We also show that the expression of sma-10 in either hypodermis or intestine fully rescues the wild-type immune response. Our results contribute to understanding the role of SMA-10 as a context-dependent component of TGF-ß Sma/Mab, and reveal a function of SMA-10 in immunity in association to the Insulin/insulin-like growth factor signalling (IIS) pathway.
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Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/imunologia , Caenorhabditis elegans/metabolismo , Imunomodulação , Proteínas de Membrana/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo , Alelos , Animais , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Endorreduplicação/imunologia , Imunidade Inata , Longevidade , Mutação com Perda de Função , Proteínas de Membrana/genética , Mutação , Receptor de Insulina/metabolismoRESUMO
INTRODUCTION: functional gastrointestinal disorders are prevalent and resource consuming. The use of group-consultations in these diseases is limited and no specific multidisciplinary programs have been developed. METHODS: a multidisciplinary approach was used in patients with diverse functional gastrointestinal disorders attending group-consultations (group A). Five two-hour sessions were scheduled over a four-month period. Sessions consisted of a theoretical introduction (Pathophysiology, Low fodmap diet, Over the counter medications, Mediterranean diet, and Laughter therapy workshop) followed by relaxation techniques. This group was compared to a similar group of patients who received written information covering the topics discussed during the group-consultations (group B). Severity of digestive and psychological symptoms, use of drugs and adherence to the diet were the main outcomes measured. RESULTS: the mean age of participants was 43 (± 1.38) years, 78 % were female and 73 % had at least two functional gastrointestinal disorders. Sixty-two patients were included in group A and 17 in group B. The severity of gastrointestinal and psychological symptoms at baseline was similar in both groups. Globally, there was an improvement in all symptoms in both groups. The proportion of participants with severe baseline gastrointestinal symptoms or pathologic anxiety scores that showed improvement was significantly higher in group A (74 % vs 23 %, p = 0.005; 47 % vs 8 %, p = 0.02, respectively). Symptoms were reassessed at six and 12 months after the intervention in participants from group A who attended ≥ 80 % sessions and a sustained response was observed. CONCLUSIONS: group-consultations are useful and efficient to alleviate gastrointestinal and psychological symptoms in patients with functional gastrointestinal disorders.
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Gastroenteropatias , Adulto , Dieta , Feminino , Gastroenteropatias/terapia , Humanos , Qualidade de Vida , Encaminhamento e ConsultaRESUMO
Despite the fact that microRNAs (miRNAs) modulate the expression of around 60% of protein-coding genes, it is often hard to elucidate their precise role and target genes. Studying miRNA families as opposed to single miRNAs alone increases our chances of observing not only mutant phenotypes but also changes in the expression of target genes. Here we ask whether the TGF-ß signalling pathways, which control many animal processes, might be modulated by miRNAs in Caenorhabditis elegans. Using a mutant for four members of the mir-58 family, we show that both TGF-ß Sma/Mab (controlling body size) and TGF-ß Dauer (regulating dauer, a stress-resistant larval stage) are upregulated. Thus, mir-58 family directly inhibits the expression of dbl-1 (ligand), daf-1, daf-4 and sma-6 (receptors) of TGF-ß pathways. Epistasis experiments reveal that whereas the small body phenotype of the mir-58 family mutant must invoke unknown targets independent from TGF-ß Sma/Mab, its dauer defectiveness can be rescued by DAF-1 depletion. Additionally, we found a negative feedback loop between TGF-ß Sma/Mab and mir-58 and the related mir-80. Our results suggest that the interaction between mir-58 family and TGF-ß genes is key on decisions about animal growth and stress resistance in C. elegans and perhaps other organisms.
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Proteínas de Caenorhabditis elegans/genética , Regulação da Expressão Gênica , MicroRNAs/metabolismo , Fator de Crescimento Transformador beta/fisiologia , Regiões 3' não Traduzidas , Animais , Tamanho Corporal , Caenorhabditis elegans/anatomia & histologia , Caenorhabditis elegans/genética , Caenorhabditis elegans/crescimento & desenvolvimento , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Células HeLa , Humanos , Larva/genética , MicroRNAs/genética , Mutação , RNA Mensageiro/metabolismo , Transdução de Sinais , Regulação para CimaRESUMO
BACKGROUND: Data about use and effectiveness of mercaptopurine in inflammatory bowel disease are relatively limited. AIMS: To assess the possible therapeutic indications, efficacy and safety of mercaptopurine as an alternative to azathioprine in inflammatory bowel disease. METHODS: Retrospective observational study in patients treated with mercaptopurine in a total cohort of 1,574 patients with inflammatory bowel disease. RESULTS: One hundred and fifty-two patients received mercaptopurine, 15.7% of these patients as an initial thiopurine, 5.3% after azathioprine failure, and 79% after azathioprine intolerance. In 52.6% of patients (n = 80), adverse effects of mercaptopurine occurred, resulting in withdrawal in 49 of them. Mercaptopurine was effective in 39% of cases (95% CI 31-48%). In the remaining patients, failure was due mainly to withdrawal due to side effects (55.1%) and therapeutic step-up (33.7%). The average total time of mercaptopurine exposure was 36 months (IQR: 2-60). Myelotoxicity with mercaptopurine was more common in patients with intermediate TPMT activity than in those with normal activity (p = 0.046). CONCLUSIONS: In our setting, mercaptopurine is primarily used as a rescue therapy in patients with azathioprine adverse effects. This could explain its modest efficacy and the high rate of adverse effects. However, this drug is still an alternative in this group of patients, before a therapeutic step-up to biologics is considered.
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Imunossupressores/uso terapêutico , Doenças Inflamatórias Intestinais/tratamento farmacológico , Mercaptopurina/uso terapêutico , Adulto , Idoso , Azatioprina/efeitos adversos , Azatioprina/uso terapêutico , Estudos de Coortes , Doença de Crohn/tratamento farmacológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Falha de TratamentoRESUMO
Nanoparticles formed within an ablation plume produced by the impact of a nanosecond laser pulse on the surface of an aluminum target have been directly measured using small-angle x-ray scattering. The target was immersed in an oxygen-nitrogen gas mixture at atmospheric pressure with the O_{2}/N_{2} ratio being precisely controlled. The results for an increasing oxygen content reveal remarkable effects on the morphology of the generated particles, which include a decrease in the particle volume but a marked increase in its surface ruggedness. Molecular dynamics simulations using a reactive potential and performed under similar conditions as the experiment reproduce the experimental trends and show in detail how the shape and surface structure of the nanoparticles evolve with increasing oxygen content. This good agreement between in situ observations in the plume and atomistic simulations emphasizes the key role of chemical reactivity together with thermodynamic conditions on the morphology of the particles thus produced.
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Although, in randomized clinical trials, once-weekly subcutaneous semaglutide (OW s.c.) has demonstrated superior efficacy in comparison with placebo and active controls in terms of glycemic control and body weight reduction in patients with type 2 diabetes mellitus (T2DM), these results need to be confirmed in a real-world (RW) setting. An RW ambispective study (6 months retrospective and 6 months prospective) was conducted in 10 tertiary hospitals in Spain. We evaluated changes in HbA1c and body weight in patients with T2DM treated with semaglutide OW s.c. Additionally, we analyzed different subgroups of patients treated with semaglutide OW s.c. as an add-on to glucose-lowering therapy. A total of 752 patients with a mean age of 60.2 years, a mean HbA1c level of 8.5%, a mean body weight of 101.6 kg, and a mean T2DM duration of 10 years were included. At 12 months, compared with baseline, there was a mean difference of -2.1% in HbA1c levels (p < 0.001) and a mean difference of 9.2 kg in body weight (p < 0.001). Moreover, there were statistically significant differences (p < 0.001) between baseline and month 12 in both HbA1c and body weight in the four subgroups receiving semaglutide OW s.c. as an add-on to glucose-lowering therapy. Semaglutide OW s.c. was well tolerated, with gastrointestinal disorders being the most commonly reported side effects. In this RW study, 12 months of treatment with semaglutide OW s.c. in patients with T2DM was associated with significant and clinically relevant improvements in glycemic control and weight loss, regardless of the glucose-lowering therapy received, and the overall safety profile was positive.
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Diabetes Mellitus Tipo 2 , Peptídeos Semelhantes ao Glucagon , Hemoglobinas Glicadas , Hipoglicemiantes , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/sangue , Masculino , Feminino , Pessoa de Meia-Idade , Peptídeos Semelhantes ao Glucagon/administração & dosagem , Peptídeos Semelhantes ao Glucagon/efeitos adversos , Espanha , Hemoglobinas Glicadas/análise , Hipoglicemiantes/administração & dosagem , Idoso , Injeções Subcutâneas , Estudos Prospectivos , Glicemia/efeitos dos fármacos , Estudos Retrospectivos , Redução de Peso/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Resultado do Tratamento , Esquema de Medicação , Controle Glicêmico/métodosRESUMO
BACKGROUND: The aim of this study is to investigate the use of once-weekly semaglutide in a real population of patients with type 2 diabetes mellitus (T2DM) over 70 years in two Spanish hospitals. METHODS: An observational, retrospective, and multicenter clinical study was designed. It included 60 patients with T2DM, with a mean age of 76.5 years, 63.3% women, and a mean of 15.5 years of evolution of T2DM, all managed in the outpatient clinical setting. The primary endpoint was the change in HbA
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Objectives: Semaglutide is a glucagon-like peptide 1 receptor agonist that improves glycemic control and achieves weight loss in type 2 diabetes (T2D) patients. Subcutaneous (s.c.) semaglutide at 1 mg once weekly (OW) is safe in T2D patients with chronic kidney disease (CKD). Whether or not CKD and its severity influence treatment response remains undetermined. Method: This is an observational, ambispective, multicenter, nationwide, real-world study designed to compare safety/efficacy of OW s.c. 1 mg semaglutide in T2D patients with or without CKD. The influence of CKD severity was also addressed. Patients were followed up for 12 months. Primary end-points were glycosylated hemoglobin (HbA1c), weight, and renal outcomes. Secondary end-points included insulin resistance, atherogenic and hepatic steatosis indexes, and changes in antihyperglycemic medications. Results: A total of 296 and 190 T2D patients without or with CKD, respectively, were recruited. Baseline CKD risk was moderate, high, or very high in 82, 53, and 45 patients, respectively. Treatment reduced HbA1c by 0.90%-1.20%. Relevant differences were seen neither between non-CKD and CKD patients nor among CKD subgroups. Notable weight losses were achieved in both non-CKD and CKD patients. The median reduction was higher in the former at 6 months (5.90 kg vs. 4.50 kg, P = 0.008) and at end of study (6.90 kg vs. 5.00 kg, P = 0.087). A trend toward slightly lower weight losses as CKD severity increased was observed. CKD markers improved across all CKD subgroups. Relevant differences were not observed for other variables, either between non-CKD and CKD patients, or among CKD subgroups. Safety concerns were not reported. Conclusion: The safety/efficacy of OW s.c. semaglutide to improve glycemic control and weight in T2D patients with CKD is not notably lower than that in T2D patients without renal failure. CKD severity barely influences treatment response. OW s.c. semaglutide can be useful to manage T2D patients with CKD in daily clinical practice.
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Diabetes Mellitus Tipo 2 , Insuficiência Renal Crônica , Humanos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hemoglobinas Glicadas , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/tratamento farmacológico , Redução de PesoRESUMO
Spry2 is a molecular modulator of tyrosine kinase receptor signaling pathways that has cancer-type-specific effects. Mammalian Spry2 protein undergoes tyrosine and serine phosphorylation in response to growth factor stimulation. Spry2 expression is distinctly altered in various cancer types. Inhibition of the proteasome functionality results in reduced intracellular Spry2 degradation. Using in vitro and in vivo assays, we show that protein kinase D (PKD) phosphorylates Spry2 at serine 112 and interacts in vivo with the C-terminal half of this protein. Importantly, missense mutation of Ser112 decreases the rate of Spry2 intracellular protein degradation. Either knocking down the expression of all three mammalian PKD isoforms or blocking their kinase activity with a specific inhibitor contributes to the stabilization of Spry2 wild-type protein. Downregulation of CSN3, a component of the COP9/Signalosome that binds PKD, significantly increases the half-life of Spry2 wild-type protein but does not affect the stability of a Spry2 after mutating Ser112 to the non-phosphorylatable residue alanine. Our data demonstrate that both PKD and the COP9/Signalosome play a significant role in control of Spry2 intracellular stability and support the consideration of the PKD/COP9 complex as a potential therapeutic target in tumors where Spry2 expression is reduced.
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Objectives: To investigate the use of once-weekly semaglutide in a real population of people with type 2 diabetes mellitus (T2DM) in three Spanish hospitals. Method: An observational, retrospective and multicenter clinical study was designed that included 166 participants with T2DM, distinguishing between a group naïve to GLP-1RA (n=72) and another switching from another GLP-1RA (n=94), all managed in the outpatient clinical setting. The primary endpoint was the change in HbA1c from baseline to the end of the study. The secondary endpoints included changes in body weight and the proportion of people with T2DM, achieving HbA1c <7.0% and body weight loss >5%. Results: After 24 months of follow-up, the reductions in HbA1c were -0.91 ± 0.7% (p<0.001) in the total cohort, -1.13 ± 1.38% (p<0.019) for GLP-1RA-naïve participants, and -0.74 ± 0.9% (p<0.023) for GLP-1RA-experienced participants. Body weight reductions were -12.42 ± 9.1% in GLP-1RA-naïve participants vs. -7.65 ± 9.7% in GLP-1RA-experienced participants (p<0.001). In the total cohort, 77.1% reached the objective of an HbA1c level <7%, and 12.7% reached between 7.1% and 7.5%. Additionally, 66.9% achieved a weight reduction ≥5%. Of all cohort, 90% received 1 mg of semaglutide once a week. The reported adverse events were consistent with the known safety profile of semaglutide. Conclusions: In routine clinical practice in Spain, the use of semaglutide once a week was associated with statistically significant and clinically relevant improvements in HbA1c and body weight in a wide range of adults with T2DM, without notable adverse effects, which supports real-world use.
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Diabetes Mellitus Tipo 2 , Adulto , Instituições de Assistência Ambulatorial , Peso Corporal , Diabetes Mellitus Tipo 2/tratamento farmacológico , Peptídeos Semelhantes ao Glucagon , Hemoglobinas Glicadas/análise , Humanos , Hipoglicemiantes/efeitos adversos , Estudos Retrospectivos , Espanha/epidemiologiaRESUMO
Background: Semaglutide [glucagon-like peptide-1 receptor-agonist (GLP-1RA)] has shown nephroprotective effects in previous cardiovascular studies. However, its efficacy and safety in patients with chronic kidney disease (CKD) and type 2 diabetes (T2D) have been rarely studied. Methods: This is a multicenter, retrospective, observational study in patients with T2D and CKD with glycosylated hemoglobin A1c (HbA1c) of 7.5-9.5% treated with subcutaneous semaglutide for 12 months in real-world clinical practice. The main objectives were glycemic control as HbA1c <7% and weight loss >5%. Results: We studied a total of 122 patients, ages 65.50 ± 11 years, 62% men, duration of T2D 12 years, baseline HbA1c 7.57% ± 1.36% and an estimated glomerular filtration rate (eGFR) 50.32 ± 19.21 mL/min/1.73 m2; 54% had a urinary albumin:creatinine ratio (UACR) of 30-300 mg/g and 20% had a UACR >300 mg/g. After 12 months of follow-up, HbA1c declined -0.73% ± 1.09% (P < .001), with 57% of patients achieving values <7% and weight loss of -6.95 kg (P < .001), with 59% of patients showing a reduction of >5% of their body weight. Systolic and diastolic blood pressure decreased -9.85 mmHg and -5.92 mmHg, respectively (P < .001). The mean UACR decreased 51% in the group with baseline macroalbuminuria (UACR >300 mg/g). The mean eGFR (by the Chronic Kidney Disease Epidemiology Collaboration) remained stable. The need for basal insulin decreased 20% (P < .005). Only 7% of patients on insulin had mild hypoglycemic episodes. Semaglutide was stopped in 5.7% of patients for digestive intolerance. Conclusions: In this real-world study, patients with T2D and CKD treated with subcutaneous semaglutide for 12 months significantly improved glycemic control and decreased weight. Albuminuria decreased by >50% in patients with macroalbuminuria. The administration of GLP-1RA in patients with T2D and CKD was safe and well tolerated.
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The new generation of organoids derived from human pluripotent stem cells holds a promising strategy for modeling host-bacteria interaction studies. Organoids recapitulate the composition, diversity of cell types, and, to some extent, the functional features of the native organ. We generated lung bud organoids derived from human embryonic stem cells to study the interaction of Streptococcus pneumoniae (pneumococcus) with the alveolar epithelium. Invasive pneumococcal disease is an important health problem that may occur as a result of the spread of pneumococcus from the lower respiratory tract to sterile sites. We show here an efficient experimental approach to model the main events of the pneumococcal infection that occur in the human lung, exploring bacterial adherence to the epithelium and internalization and triggering an innate response that includes the interaction with surfactant and the expression of representative cytokines and chemokines. Thus, this model, based on human minilungs, can be used to study pneumococcal virulence factors and the pathogenesis of different serotypes, and it will allow therapeutic interventions in a reliable human context. IMPORTANCE Streptococcus pneumoniae is responsible for high morbidity and mortalities rates worldwide, affecting mainly children and adults older than 65 years. Pneumococcus is also the most common etiologic agent of bacterial pneumonia and nonepidemic meningitis, and it is a frequent cause of bacterial sepsis. Although the introduction of pneumococcal vaccines has decreased the burden of pneumococcal disease, the rise of antibiotic-resistant strains and nonvaccine types by serotype replacement is worrisome. To study the biology of pneumococcus and to establish a reliable human model for pneumococcal pathogenesis, we generated human minilungs from embryonic stem cells. The results show that these organoids can be used to model some events occurring during the interaction of pneumococcus with the lung, such as adherence, internalization, and the initial alveolar innate response. This model also represents a great alternative for studying virulence factors involved in pneumonia, drug screening, and other therapeutic interventions.
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Células-Tronco Embrionárias Humanas , Infecções Pneumocócicas , Adulto , Criança , Células-Tronco Embrionárias Humanas/metabolismo , Humanos , Pulmão , Infecções Pneumocócicas/microbiologia , Vacinas Pneumocócicas , Streptococcus pneumoniae , Fatores de Virulência/metabolismoRESUMO
Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) are indicated in type 2 diabetes and obesity for their high efficacy in controlling glycaemia and inducing body weight loss, respectively. Patients may develop gastrointestinal adverse events (GI AEs), namely nausea, vomiting, diarrhoea and/or constipation. To minimize their severity and duration, healthcare providers (HCPs) and patients must be aware of appropriate measures to follow while undergoing treatment. An expert panel comprising endocrinologists, nephrologists, primary care physicians, cardiologists, internists and diabetes nurse educators convened across virtual meetings to reach a consensus regarding these compelling recommendations. Firstly, specific guidelines are provided about how to reach the maintenance dose and how to proceed if GI AEs develop during dose-escalation. Secondly, specific directions are set about how to avoid/minimize nausea, vomiting, diarrhoea and constipation symptoms. Clinical scenarios representing common situations in daily practice, and infographics useful to guide both HCPs and patients, are included. These recommendations may prevent people with T2D and/or obesity from withdrawing from GLP-1 RAs treatment, thus benefitting from their superior effect on glycaemic control and weight loss.
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Background: The impact of glucagon-like peptide-1 receptor agonists on patients with heart failure has not been fully described. Our main objective was to evaluate the safety and clinical and glycemic efficacy of once-weekly semaglutide in obese patients with type 2 diabetes and heart failure. Methods: In this observational, retrospective, real-world study, we enrolled outpatients with type 2 diabetes, obesity, and heart failure who started semaglutide and were followed-up on at 3, 6, and 12 months. Results: A total of 136 patients were included. From baseline to 12 months, there was a significant improvement on the Kansas City Cardiomyopathy Questionnaire total symptom score (59.0 ± 24.1 vs 79.9 ± 28.4 points, p<0.01), a reduction in the proportion of patients with New York Heart Association functional class III (40.4% to 16.2%, p<0.01), and a reduction in N-terminal pro-brain natriuretic peptide levels (969.5 ± 653.5 vs 577.4 ± 322.1 pg/mL, p<0.01). Emergency department visits due to heart failure, hospitalizations due to heart failure, and all-cause hospitalizations also declined. Additionally, significant reductions in glycated hemoglobin (-1.4%) and body weight (-12.7 kilograms) were observed as well as a de-intensification of antidiabetic therapy. Moreover, semaglutide was safe and well-tolerated. Conclusion: In obese patients with type 2 diabetes and heart failure, the use of once-weekly semaglutide was safe and clinically efficacious, improving health and functional status. Nevertheless, more strong evidence on glucagon-like peptide-1 receptor agonists in heart failure is required.
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Diabetes Mellitus Tipo 2 , Insuficiência Cardíaca , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Peptídeos Semelhantes ao Glucagon/uso terapêutico , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/tratamento farmacológico , Humanos , Obesidade/induzido quimicamente , Obesidade/complicações , Obesidade/tratamento farmacológico , Estudos RetrospectivosRESUMO
We conducted a retrospective observational study to demonstrate that switching to insulin degludec from other long-acting insulins reduces the risk of hypoglycaemia events and improves glycaemic control in patients with type 2 diabetes and stage 2-3B chronic kidney disease.
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Glicemia/análise , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemia/prevenção & controle , Insulina de Ação Prolongada/uso terapêutico , Insuficiência Renal Crônica/tratamento farmacológico , Idoso , Diabetes Mellitus Tipo 2/complicações , Feminino , Humanos , Hipoglicemia/induzido quimicamente , Hipoglicemiantes/uso terapêutico , Masculino , Pessoa de Meia-Idade , Prognóstico , Insuficiência Renal Crônica/complicações , Estudos Retrospectivos , Fatores de RiscoRESUMO
Gene therapy is being investigated for a range of serious lung diseases, such as cystic fibrosis and emphysema. Recombinant adeno-associated virus (rAAV) is a well-established, safe, viral vector for gene delivery with multiple naturally occurring and artificial serotypes available displaying alternate cell, tissue, and species-specific tropisms. Efficient AAV serotypes for the transduction of the conducting airways have been identified for several species; however, efficient serotypes for human lung parenchyma have not yet been identified. Here, we screened the ability of multiple AAV serotypes to transduce lung bud organoids (LBOs)-a model of human lung parenchyma generated from human embryonic stem cells. Microinjection of LBOs allowed us to model transduction from the luminal surface, similar to dosing via vector inhalation. We identified the naturally occurring rAAV2 and rAAV6 serotypes, along with synthetic rAAV6 variants, as having tropism for the human lung parenchyma. Positive staining of LBOs for surfactant proteins B and C confirmed distal lung identity and suggested the suitability of these vectors for the transduction of alveolar type II cells. Our findings establish LBOs as a new model for pulmonary gene therapy and stress the relevance of LBOs as a viral infection model of the lung parenchyma as relevant in SARS-CoV-2 research.
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Dependovirus/genética , Terapia Genética/métodos , Células-Tronco Embrionárias Humanas/citologia , Pneumopatias/terapia , Organoides/citologia , Linhagem Celular , Dependovirus/imunologia , Técnicas de Transferência de Genes , Vetores Genéticos/genética , Humanos , Pulmão/metabolismo , Modelos Biológicos , Tecido Parenquimatoso/citologiaRESUMO
Sos1 is an universal, widely expressed Ras guanine nucleotide-exchange factor (RasGEF) in eukaryotic cells. Its N-terminal HD motif is known to be involved in allosteric regulation of Sos1 GEF activity through intramolecular interaction with the neighboring PH domain. Here, we searched for other cellular proteins also able to interact productively with the Sos1 HD domain. Using a yeast two-hybrid system, we identified the interaction between the Sos1 HD region and CSN3, the third component of the COP9 signalosome, a conserved, multi-subunit protein complex that functions in the ubiquitin-proteasome pathway to control degradation of many cellular proteins. The interaction of CSN3 with the HD of Sos1 was confirmed in vitro by GST pull-down assays using truncated mutants and reproduced in vivo by co-immunoprecipitation with the endogenous, full-length cellular Sos1 protein. In vitro kinase assays showed that PKD, a COP9 signalosome-associated-kinase, is able to phosphorylate Sos1. The intracellular levels of Sos1 protein were clearly diminished following CSN3 or PKD knockdown. A sizable fraction of the endogenous Sos1 protein was found ubiquitinated in different mammalian cell types. A significant reduction of RasGTP formation upon growth factor stimulation was also observed in CSN3-silenced as compared with control cells. Our data suggest that the interaction of Sos1 with the COP9 signalosome and PKD plays a significant role in maintenance of cellular Sos1 protein stability and homeostasis under physiological conditions and raises the possibility of considering the CSN/PKD complex as a potential target for design of novel therapeutic drugs.